WASHINGTON, D.C. -- Airlines continue to be squeezed by high fuel prices, by personnel costs and by pressure from competitors. To survive, many carriers have chosen to delay replacing their aging fleets with newer-model aircraft.

While it is true that the life of commercial airplanes can be extended nearly indefinitely through rigorous maintenance programs, small, undetectable and potentially catastrophic fractures can and do occasionally occur in the airframes of older aircraft. This has raised the concern of both airline passenger groups and associations representing airline flight crews. Now, the United States Air Transport Federation (USATF), an airline trade association, has taken the lead in working out a deal among these concerned parties.

The USATF announced today that over the past six years it has been working closely with the Federal Aviation Administration (FAA) to develop an algorithm that takes into account each airplane's flying history to predict the risk of it developing a catastrophic failure. As that risk increases toward an unacceptable level, an "expiration date" is determined for that particular aircraft.

Sources inside the USATF have told Err Travel that beginning next year, all commercial airplanes carrying more than 15 passengers and flying into or out of an airport within the United States must post an expiration date on the fuselage, displayed prominently so that it is clearly visible to boarding passengers.

In explaining the methodology behind determining expiration dates, Dorothy Beckwerth, spokesperson for the USATF said, "An expiration date is based on over 800 factors of aircraft operation. Some of those factors are obvious: the date that the aircraft was placed in service, the number of hours of operation, the number of takeoffs and landings.

"Other factors," said Beckwerth, "are less obvious. For example, the amount of fluid pumped from the lavatories, the number of times the aircraft has been painted, the directions in which the aircraft has flown, the brands of beer served passengers and crew and the number of in-flight movies in which Owen Wilson has appeared are also taken into account when determining an expiration date."

When asked what will happen once an aircraft reaches its expiration date, Beckwerth said, "We expect that passengers will choose to fly or not based on their level of risk tolerance, just as they would choose to drink from a carton of milk or eat from a can of peas that have passed their expiration dates. If you are asking if we will be taking out of service those aircraft that have reached their expiration dates, the answer is no.”